Return Laser Pulses (video) Princeton University, Engineering School Loading video... Caption Researchers at Princeton University developed a technique for generating a laser beam out of nothing but air. They focus a pump laser on a distant point in the air and another laser beam comes back. The video shows 100 pulses of infra-red light from this "air laser." The center region represents the highest intensity; the outer areas have lower intensity light. The technique could be used for sensing minute quantities of gas in the air from a distance. Credit Image courtesy Arthur Dogariu, Princeton University Usage Restrictions For non-commercial use only Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.